Protein hierarchical clustering analysis for DEPs
A hierarchical clustering was carried out to gain a systematic overview of the expression dynamics of the 74 DEPs resulted from different Ca level treatments. In this analysis, proteins showed similar expression patterns were grouped together. As shown in Figure 4, approximate two-thirds of the 74 DEPs were down-regulated or remain stable under low Ca treatment. While, the expression abundances of these proteins increased under high Ca application. These proteins mainly belong to photosynthesis, energy production, material nitrogen, transcription and signaling, and heat shock proteins. The expression dynamics of these proteins suggested Ca deficiency probable distributed these biological processes while adequate exogenous Ca supply facilitated these processes. We also observed that some proteins showed stable or even increased abundance under low Ca condition, while displayed significantly reduced abundance in high Ca level environment. The numbers of this group included a variety of redox homeostasis related proteins and chaperonin proteins.